CASE Pregnant woman with herpes simplex virus
A 26-year-old primigravid woman at 12 weeks of gestation indicates that she had an initial episode of herpes simplex virus (HSV) 6 years prior to presentation. Subsequently, she has had 1 to 2 recurrent episodes each year. She asks about the implications of HSV infection in pregnancy, particularly if anything can be done to prevent a recurrent outbreak near her due date and reduce the need for a cesarean delivery.
How would you counsel this patient?
Meet our perpetrator
Herpes simplex virus (HSV), the most prevalent sexually transmitted infection, is a DNA virus that has 2 major strains: HSV-1 and HSV-2. HSV-1 frequently is acquired in early childhood through nonsexual contact and typically causes orolabial and, less commonly, genital outbreaks. HSV-2 is almost always acquired through sexual contact and causes mainly genital outbreaks.1
There are 3 classifications of HSV infection: primary, initial-nonprimary, and recurrent (TABLE).
Primary infection refers to infection in a person without antibodies to either type of HSV.
Initial-nonprimary infection refers to acquisition of HSV-2 in a patient with preexisting antibodies to HSV-1 or vice versa. Patients tend to have more severe symptoms with primary as opposed to initial-nonprimary infection because, with the latter condition, preexisting antibodies provide partial protection against the opposing HSV type.1 According to the Centers for Disease Control and Prevention, the seroprevalence of HSV-1 has decreased by approximately 23% in adolescents aged 14 to 19 years, with a resultant increase in the number of primary HSV-1 genital infections through oral-sexual contact in adulthood.2
Recurrent infection refers to reactivation of the same HSV type corresponding to the serum antibodies.
Clinical presentation
After an incubation period of 4 to 7 days, symptomatic patients with primary and initial-nonprimary genital HSV infections typically present with multiple, bilateral genital lesions at various stages of development. These lesions begin as small erythematous macules and then progress to papules, vesicles, pustules, ulcers, and crusted scabs over a period of 3 to 6 weeks1 (FIGURE). Patients also may present with fever, headache, fatigue, dysuria, and painful inguinal lymphadenopathy. Patients with recurrent infections usually experience prodromal itching or tingling for 2 to 5 days prior to the appearance of unilateral lesions, which persist for only 5 to 10 days. Systemic symptoms rarely are present. HSV-1 genital infection has a symptomatic recurrence rate of 20% to 50% within the first year, while HSV-2 has a recurrence rate of 70% to 90%.1
The majority of primary and initial-nonprimary infections are subclinical. One study showed that 74% of HSV-1 and 63% of HSV-2 initial genital herpes infections were asymptomatic.3 The relevance of this observation is that patients may not present for evaluation unless they experience a symptomatic recurrent infection. Meanwhile, they are asymptomatically shedding the virus and unknowingly transmitting HSV to their sexual partners. Asymptomatic viral shedding is more common with HSV-2 and is the most common source of transmission.4 The rate of asymptomatic shedding is unpredictable and has been shown to occur on 10% to 20% of days.1
Diagnosis and treatment
The gold standard for diagnosing HSV infection is viral culture; however, polymerase chain reaction (PCR) assays are faster to result and more sensitive.4,5 Both culture and PCR studies can distinguish the HSV type, allowing physicians to counsel patients regarding the expected clinical course, rate of recurrence, and implications for future pregnancies. After an initial infection, it may take up to 12 weeks for patients to develop detectable antibodies. Therefore, serology can be quite useful in determining the timing and classification of the infection. For example, a patient with HSV-2 isolated on viral culture or PCR and HSV-1 antibodies identified on serology is classified as having an initial-nonprimary infection.4
HSV treatment is dependent on the classification of infection. Treatment of primary and initial-nonprimary infection includes:
- acyclovir 400 mg orally 3 times daily
- valacyclovir 1,000 mg orally twice daily, or
- famciclovir 250 mg orally 3 times daily for 7 to 10 days.
Ideally, treatment should be initiated within 72 hours of symptom onset.
Recurrent infections may be treated with:
- acyclovir 400 mg orally three times daily for 5 days
- valacyclovir 1,000 mg orally once daily for 5 days, or
- famciclovir 1,000 mg orally every 12 hours for 2 doses.
Ideally, treatment should begin within 24 hours of symptom onset.4,6
Patients with immunocompromising conditions, severe/frequent outbreaks (>6 per year), or who desire to reduce the risk of transmission to HSV-uninfected partners are candidates for chronic suppressive therapy. Suppressive options include acyclovir 400 mg orally twice daily, valacyclovir 500 mg orally once daily, and famciclovir 250 mg orally twice daily. Of note, there are many regimens available for acyclovir, valacyclovir, and famciclovir; all have similar efficacy in decreasing symptom severity, time to lesion healing, and duration of viral shedding.6 Acyclovir generally is the least expensive option.4
Continue to: Pregnancy and prevention...